Question

Problema 8 multumesc anticipat

Answer 1

ai rezolvarea în imagine

Answer 2

Fie n - numărul copiilor.

[tex]\it \dfrac{c_1+c_2+c_3+\ ...\ +c_n}{n} = 11 \Rightarrow c_1+c_2+c_3+\ ...\ +c_n =11n \\\;\\ \\\;\\ c_1+c_2+c_3+\ ...\ +c_{n-1} +17 = 11n \Rightarrow \\\;\\ \\\;\\ \Rightarrow c_1+c_2+c_3+\ ...\ +c_{n-1} =11n - 17 \ \ \ \ \ (1)[/tex]


[tex]\it \dfrac{c_1+c_2+c_3+\ ...\ +c_{n-1} }{n-1} = 10 \Rightarrow \\\;\\ \\\;\\ \Rightarrow c_1+c_2+c_3+\ ...\ +c_{n-1} =10n-10 \ \ \ \ \ (2)[/tex]


$\it (1),\ (2) \Rightarrow 11n - 17 = 10n-10 \Rightarrow 11n-10n=17-10 \Rightarrow n = 7$